Hyundai Motor Group has developed the world’s first Active Shift Control (ASC) transmission technology, which is said to optimise transmission efficiency. The system monitors gearshifts 500 times per second, precisely adjusting the transmission rotation speed for faster shift times.
The new technology will make its debut in the upcoming Hyundai Sonata Hybrid and will eventually trickle down to other, more affordable Hyundai and Kia hybrids.
The ASC tech applies new control logic software to the Hybrid Control Unit (HCU). This then controls the electric motor so that it aligns the rotational speeds of the engine and transmission to reduce gear shift time by 30 percent. The technology also delivers smoother gear changes despite quicker shift times.
“The development of world’s first ASC technology is a remarkable innovation which incorporates precise motor control to automatic transmissions,” said KyoungJoon Chang, Vice President and Head of Powertrain Control System Group of Hyundai Motor Group, “It will not only save fuel but also provide a more fun driving experience for our customers.”
Reducing gear shift time by 30 percent
Conventional hybrid vehicles do not have torque convertors in order to further improve fuel economy as torque convertors lose energy during the process of transmission. Although fuel efficient, such a system also requires longer shift times to ensure smoother gear changes. The ASC tech helps to mitigate these losses thanks to the new control logic software to the HCU that syncs the rotational speeds of the engine and transmission.
With the synchronisation, shift time is reduced by 30 percent from 500ms to 350ms. This not only improves hybrid vehicle’s acceleration performance and fuel economy, but also durability of the transmission by minimising friction during gearshift.
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